Disc brake systems for heavy-duty vehicles are known. Such disc brake systems operate by forcing a pair of opposing brake pads against a rotor to create friction between the pads and the rotor which enables slowing and/or stopping of the vehicle. More particularly, a disc brake system includes a plurality of disc brake assemblies, in which each disc brake assembly is operatively mounted on or adjacent a wheel end of the heavy-duty vehicle.
Typically, each disc brake assembly includes a carrier, which supports a caliper that is described in greater detail below. The carrier is attached to a torque plate, typically by mechanical fasteners, such as bolts. The torque plate in turn is rigidly connected to an axle of an axle/suspension system of the vehicle, such as by welding. The torque plate is located on or adjacent a wheel end of the heavy-duty vehicle. The torque plate resists the torque that is generated during braking, and maintains proper alignment of the carrier and caliper to ensure proper operation of the components of the brake assembly.
The caliper is formed with a bore for receiving one or more pistons and an actuator. The actuator typically has an air chamber, referred to in the art as a brake chamber, which is in fluid communication with a compressed air source and activates movement of the piston(s). The caliper also includes an outboard pad seat that is disposed opposite the piston(s). Each one of a pair of opposing brake pads includes friction material that is mounted on a backing plate, and is seated in the carrier, with one of the pads being adjacent the piston(s) and the other pad being adjacent the outboard pad seat. Upon actuation by the brake chamber, the piston(s) and the outboard pad seat cooperate to control movement of the brake pads.
The rotor includes a disc portion, which is disposed between the brake pads in a manner that allows the friction material of each pad to face a respective one of a pair of surfaces of the disc portion. The rotor also includes a mounting portion that is adapted for mounting to a respective one of the wheel end assemblies of the vehicle by mechanical fasteners, such as bolts. A sleeve typically is integrally formed with and extends between the disc portion of the rotor and the mounting portion of the rotor. This construction enables the rotor to be operatively mounted on the wheel end assembly for rotation and connection to its respective vehicle wheel.
During vehicle travel, when the vehicle brake system is engaged, compressed air flows to the brake chamber, which causes movement of the piston(s), typically through a mechanism, and the outboard pad seat, which in turn forces the friction material of the pads against the disc portion of the rotor, slowing and/or stopping rotation of the rotor, thereby slowing and/or stopping rotation of the vehicle wheel.
The manner in which and where the prior art actuator is mounted has some disadvantages and drawbacks. The prior art actuator was attached directly to the caliper in a cantilevered fashion by a pair of mounting studs, using no other support structure. Such cantilevered mounting of the prior art actuator provides less than optimum support of the actuator, and also undesirably creates stress on the caliper. In addition, in order to enable the caliper to have sufficient strength and rigidity to support such cantilevered mounting configuration of the brake chamber, the size and weight of the caliper must be undesirably increased. The cost corresponding to the manufacture of the caliper, thus, may be undesirably high.
Most prior art actuators are mounted on the inboard side of the caliper. Because of this orientation and the space constraints in a brake system and corresponding axle/suspension system, the prior art actuator and caliper typically are located behind and/or beneath the beam of the axle/suspension system. This location potentially creates an undesirable level of clearance between the prior art actuator and the ground, which could potentially result in the prior art actuator being damaged by hitting the ground or being struck with road debris.
The disadvantages and drawbacks associated with the mounting of prior art actuators make it desirable to develop an improved way to mount actuators on a heavy-duty vehicle. As a result, there is a need for a brake actuator of an air disc brake system for heavy-duty vehicles to be mounted in a manner that provides improved support of the brake actuator and improved protection of the brake chamber, while potentially reducing the size and weight of the caliper. The apparatus for remote mounting of an air disc brake actuator of the subject disclosure satisfies these needs.